1. Field of the Invention
This invention relates to hair conditioning compositions intended to be rinsed off and containing non-volatile insoluble silicone gum, particularly dimethiconol gum.
2. The Related Art
Use of high viscosity gums as hair conditioning agents is known and suitable gums are described in U.S. Pat. No. 4,152,416 (Spitzer). The gums are usually used in solution in a volatile silicone such as a cyclomethicone.
Emulsion polymerised silicones are known from U.S. Pats. No. 2,891,920 (Hyde), 3,294,725 (Findlay), and 3,360,491 (Axon).
Emulsion polymerised dimethylpolysiloxane microemulsions are described in EP 0 268 982 (Toray). Dimethiconol materials are taught as one of a range of possibilities.
Articles such as "Organofunctional Silicones for Personal Care Applications", Wendel, Samuel R and DiSapio, Alfred J. Cosmetics & Toiletries vol 98 May 1983, pp 103-106 have taught away from the use of Dimethiconol in hair compositions.
Dimethiconol can be prepared in various ways, one of which is emulsion polymerisation.
Silicone oils are often added to hair conditioning compositions in the form of aqueous emulsions. These emulsions are usually formed by mechanical shearing of the oil. Sometimes they are formed by chemical emulsification but this is not the same as emulsion polymerisation and does not provide the unexpected advantages of the present invention.
A problem with prior hair conditioning compositions has been that they either provide inadequate conditioning; or the use of high viscosity gums leads to processing difficulties. The latter problem has in the past been partially solved by the use of solvent for the gum. Such solvents are undesirable for the consumer and affect the conditioning properties of the gum.